Social phobia is a chronic, debilitating, prevalent condition for which few effective treatments exist. The only medication established to be effective in a large double blind trial is the monoamine oxidase inhibitor phenelzine. Recent studies with phenelzine suggest that approximately 65% of social phobic patients improve significantly with treatment, but a high incidence of impaired function due to adverse effects now this medication intolerable for marry patients. Moclobemide is a type A specific reversible MAOI which has been marketed as an ant in Europe but not in the U.S. In therapeutic trials with more than 2000 patients, it has been shown to be effective for depression with less adverse effects than other MAOIs or tricyclics. One double blind controlled study of moclobemide in patients with social phobia suggests that moclobemide is equally effective as phenelzine and is far better tolerated. Tyramine challenge studies indicate that there is far less risk of hypertensive crisis with moclobemide than with marketed MAOIs. Nevertheless, trials of moclobemide in social phobia have not attracted financial sponsorship from the American manufacturer. In this proposal, 90 social phobic patients will be entered to be treated on an outpatient double blind basis with either moclobemide or placebo for 8 weeks, and responders will continue for an additional 8 weeks. Outcome will be rated on a double-blind basis by an independent evaluator who will also be blind to any adverse effects. Adverse effects will be rated by the treating psychiatrist. When completed, the study should provide an objective t of the efficacy and safety of moclobemide in social phobia.